Got tuned!
Got tuned! Chuck from HPE came out to Utah yesterday to do a group tune. My computer is pretty much maxed out at 4600 rpms so we couldn't run it up any higher but here are the results.
http://www.youtube.com/watch?v=AcX8s2YI_rQ
http://www.youtube.com/watch?v=AcX8s2YI_rQ
Staging Lane
Joined: Jul 2006
Posts: 93
Likes: 0
The conventional wisdom is that the stock computer isn't maxed out until 7K. I'm guessing you've got other problems (valve float?, ignition insufficiency with boost?, something).
The other thing is, those numbers seem awfully high.
You might want to add some details about your engine, like what cam, heads, intake, exhaust, transmixer, stall, gears, etc. you're running, in the event you really want comments. although I fear you're not going to like what's coming...
Best -- Gary
The other thing is, those numbers seem awfully high.
You might want to add some details about your engine, like what cam, heads, intake, exhaust, transmixer, stall, gears, etc. you're running, in the event you really want comments. although I fear you're not going to like what's coming...
Best -- Gary
Yeah that thing pulled smooth as a babys *** right until 4600-4700 RPM... Thats not the computer being maxed out...
Like Z48LT-1 said, looks like valve float or something to that effect... Although he is right about the ignition insufficiency, it would cause a graph somewhat like that.
Like Z48LT-1 said, looks like valve float or something to that effect... Although he is right about the ignition insufficiency, it would cause a graph somewhat like that.
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Verdad Gallardo I don't know if its freakin out due to a mechanical problem or not, he made 14 pulls trying to fix it and he said the VE and power enrichment tables are maxed out and he can't add anything more at that point and he said its pretty much at the limits of the stock pcm?
Here is my setup: Forged 355, Ported LT4 heads/intake, 52mm tb, EPP FMIC, ATI Race Bypass, F1A, Lonnies double pumper fuel pumps, 60lb/hr injectors, full BMR suspension, Moser 9", PST ds, Mcleod street twin, Stock t56.
Here is my setup: Forged 355, Ported LT4 heads/intake, 52mm tb, EPP FMIC, ATI Race Bypass, F1A, Lonnies double pumper fuel pumps, 60lb/hr injectors, full BMR suspension, Moser 9", PST ds, Mcleod street twin, Stock t56.
Thats interesting...
I have heard of the PCM being maxed out RPM wise, but never HP wise.... But I can see the logic behind it. I am sure theres a point where you cant add anything else...
Could anyone else chime in here that may have seen the same thing?
I have heard of the PCM being maxed out RPM wise, but never HP wise.... But I can see the logic behind it. I am sure theres a point where you cant add anything else...
Could anyone else chime in here that may have seen the same thing?
Is this a new setup that you've got? Or, have you been hunting this gremlin for a while? I wonder if I could get Chuck to come in here and give us his take, as I am new to the whole tuning thing.
I have had this setup for awhile, i'm just now getting around to adding extra boost and getting a tune.I dynoed a few weeks ago on 13 psi and the pull was pretty smooth across the board.
I did take it out on the street to run it up to 4 grand and it felt amazing! It was very hard to get my foot out of the throttle haha
I have had this setup for awhile, i'm just now getting around to adding extra boost and getting a tune.I dynoed a few weeks ago on 13 psi and the pull was pretty smooth across the board.
I did take it out on the street to run it up to 4 grand and it felt amazing! It was very hard to get my foot out of the throttle haha
Looking at the graph your gaining roughly 100RWHP and 70rwtq every 500rpms, so at 6500 you would be making big power. What pulley setup do you have on it? Don't know why he would say the computer just stoped, I'm no tuner so I can't help in that department.
P.S. what inlet do you have on this blower?
P.S. what inlet do you have on this blower?
On The Tree
Joined: Sep 2005
Posts: 169
Likes: 0
I would not run the car until you figure out what's going on. To me it looks as though it's detonating big time. The problem with a factory LT-1 ECU is that it can't recognize boost pressure. Unfortunately, the tune ends up being a series of band aids. The reality is that you will never have a proper tune with the stock ECU in your application. A F.A.S.T. ECU would be the best way to go.
However, if you are running out of fuel, there are a few things you can look at that are not ecu related.
What sort of fuel system do you have on the car? (Pump, regulator, line size)
What size injector are you running?
Are you using a FMU?
However, if you are running out of fuel, there are a few things you can look at that are not ecu related.
What sort of fuel system do you have on the car? (Pump, regulator, line size)
What size injector are you running?
Are you using a FMU?
The fuel system consists of a Lonnies double pumper/hotwire kit, stock lines, stock regulator and 60lb/hr injectors and an AIS stage 2 kit with 100% meth and no FMU.
Right now i'm looking into my valvsprings. I don't even know what i'm running and those have been suggested as a possible problem.
Right now i'm looking into my valvsprings. I don't even know what i'm running and those have been suggested as a possible problem.
With that kind of hp your ve has to be way up there if its set as a 355 in the cylinder size section of the tune. The stock pcm will only let you tell it the ve is so high before it calls bs on you. The pe mode will also only allow so much enrichment to compensate at higher rpm. Stock maf would have maxed out well before you made the power you did so that method will not work either.
Basicly stock pcm hates boost and has no concessions to deal with it other than to run it as open loop in ve mode with a bunch of wierdness going on to trick it into running half right. If I was giong to the trouble of all that i'd put big stuff 3 on it and be done.
From the curve I would almost say it looks mechanical as well though, but it could very well be the stock pcm. It is likely with you running near the limits of its abilities.
Basicly stock pcm hates boost and has no concessions to deal with it other than to run it as open loop in ve mode with a bunch of wierdness going on to trick it into running half right. If I was giong to the trouble of all that i'd put big stuff 3 on it and be done.
From the curve I would almost say it looks mechanical as well though, but it could very well be the stock pcm. It is likely with you running near the limits of its abilities.
TECH Senior Member
iTrader: (3)
Joined: Oct 2006
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From: Decatur, TN (N-W of Athens)
With that kind of hp your ve has to be way up there if its set as a 355 in the cylinder size section of the tune. The stock pcm will only let you tell it the ve is so high before it calls bs on you. The pe mode will also only allow so much enrichment to compensate at higher rpm. Stock maf would have maxed out well before you made the power you did so that method will not work either.
Basicly stock pcm hates boost and has no concessions to deal with it other than to run it as open loop in ve mode with a bunch of wierdness going on to trick it into running half right. If I was giong to the trouble of all that i'd put big stuff 3 on it and be done.
From the curve I would almost say it looks mechanical as well though, but it could very well be the stock pcm. It is likely with you running near the limits of its abilities.
Basicly stock pcm hates boost and has no concessions to deal with it other than to run it as open loop in ve mode with a bunch of wierdness going on to trick it into running half right. If I was giong to the trouble of all that i'd put big stuff 3 on it and be done.
From the curve I would almost say it looks mechanical as well though, but it could very well be the stock pcm. It is likely with you running near the limits of its abilities.
I was going to say fuel starvation, but then I got to thinking, it wouldn't just peter out like that, it would hit a plateau and not gain anything. If you're planning to make more power, I'd think you might consider upgrading to aftermarket lines and have the rails bored out a bit (if it's possible, otherwise aftermarket rails).
Good luck, I'm interested in the full potential of that motor.